How is stepping motor torque calculated?

Step motor torque calculation method. When selecting a stepper motor, first of all, ensure that the output power of the stepper motor is greater than the power required by the load. When selecting power stepper motor, the load torque of mechanical system should be calculated first. The torque-frequency characteristics of the motor can meet the mechanical load and have a certain margin to ensure its operation.

In practice, the load torque at various frequencies must be within the range of torque-frequency characteristic curve. Generally speaking, a motor with a large static torque has a large load torque.

Step motor torque calculation method, select the step motor need to carry out the following calculation:

The first is to calculate the gear reduction ratio according to the required pulse equivalent, gear reduction ratio I is calculated as follows:

I =(φ.s)/(360. δ) (-) φ -- step Angle of stepping motor (O/pulse)

S -- Screw pitch (mm)

Δ - (mm/pulse)

Step motor torque calculation method, calculation table, screw and gear converted to the motor shaft inertia Jt.

Jt=J+ (/i2) [(J2+Js)+W/g (S/2π) 2) (-2)

 formula, Jt -- the inertia converted to the motor shaft (kg.cm.s2)

J, J2 -- Gear inertia (kg.cm.s2)

Js ---- screw inertia (kg.cm.s2) W-- weight of table (N)

S -- Screw pitch (cm)

The calculation method of stepping motor torque also needs to calculate the total torque M of motor output

M = Ma + Mf + Mt (3)

Ma= (Jm+Jt).n/T×.02×0ˉ2 (-4)

Where Ma - motor starting acceleration torque (N.m)

Jm, Jt-- Motor's own inertia and load inertia (kg.cm.s2)

N -- Speed required by the motor (r/min)

T-- Motor speed rise time (s)

Mf = (U.W.S)/(2 PI eta I) x 0 ˉ 2 (5)

Mf-- Friction conversion of guide rail to motor torque (N.m)

U -- Friction coefficient

η-- Transfer efficiency

Mt = (Pt) s)/(2 PI eta I) x 0 ˉ 2 (-- 6)

Mt-- Conversion of cutting force to motor torque (N.m)

Pt-- Large cutting force (N)

Step motor torque calculation method, also need to load starting frequency estimation. The starting frequency of the motor controlled by the NUMERICAL control system has a great relationship with the load torque and inertia, and its estimation formula is